package com.example.authsystem.service.impl;

import com.example.authsystem.dto.*;
import com.example.authsystem.service.StatisticsService;
import io.swagger.v3.oas.annotations.Operation;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Service;

import java.time.LocalDate;
import java.time.LocalDateTime;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;

@Slf4j
@Service
@RequiredArgsConstructor
public class StatisticsServiceImpl implements StatisticsService {

    @Override
    @Operation(summary = "获取仪表板统计", description = "获取系统总览统计数据")
    public DashboardStatsDto getDashboardStats() {
        log.info("获取仪表板统计数据");
        return DashboardStatsDto.builder()
                .totalUsers(1250L).activeUsers(980L).todayRegistrations(25L)
                .totalLogins(15600L).onlineUsers(156L).build();
    }

    @Override
    @Operation(summary = "获取用户活动统计", description = "获取指定时间范围内的用户活动数据")
    public List<UserActivityDto> getUserActivity(LocalDate startDate, LocalDate endDate) {
        log.info("获取用户活动统计: {} 到 {}", startDate, endDate);
        return Arrays.asList(
                UserActivityDto.builder().date(startDate).loginCount(234L).registrationCount(12L)
                        .activeUserCount(189L).pageViews(1567L).apiCalls(3421L).build(),
                UserActivityDto.builder().date(endDate).loginCount(256L).registrationCount(8L)
                        .activeUserCount(201L).pageViews(1789L).apiCalls(3652L).build()
        );
    }

    @Override
    @Operation(summary = "获取系统性能指标", description = "获取系统运行性能统计数据")
    public SystemMetricsDto getSystemMetrics() {
        log.info("获取系统性能指标");
        return SystemMetricsDto.builder()
                .cpuUsage(65.5).memoryUsage(72.3).diskUsage(45.8)
                .networkInbound(1024L).networkOutbound(2048L).build();
    }

    @Override
    @Operation(summary = "导出统计报表", description = "导出Excel格式的统计报表")
    public byte[] exportStatisticsReport(String reportType, LocalDate startDate, LocalDate endDate) {
        log.info("导出{}统计报表: {} 到 {}", reportType, startDate, endDate);
        String content = String.format("统计报表\n类型: %s\n时间范围: %s 到 %s\n导出时间: %s",
                reportType, startDate, endDate, LocalDateTime.now());
        return content.getBytes();
    }

    @Override
    @Operation(summary = "获取用户统计", description = "获取指定用户的统计信息")
    public UserStatsDto getUserStats(Long userId) {
        log.info("获取用户{}的统计信息", userId);
        return UserStatsDto.builder()
                .userId(userId).loginCount(45L).lastLoginTime(LocalDateTime.now().minusHours(2))
                .totalSessions(128L).avgSessionDuration(35.5).build();
    }

    @Override
    @Operation(summary = "批量获取用户统计", description = "批量获取多个用户的统计信息")
    public List<UserStatsDto> getBatchUserStats(List<Long> userIds) {
        log.info("批量获取{}个用户的统计信息", userIds.size());
        return userIds.stream().map(userId ->
                UserStatsDto.builder().userId(userId).loginCount(30L + userId)
                        .lastLoginTime(LocalDateTime.now().minusHours(userId.intValue()))
                        .totalSessions(100L + userId * 2).avgSessionDuration(40.0).build()
        ).collect(Collectors.toList());
    }

    @Override
    public UserActivityDto getUserStatistics(LocalDate startDate, LocalDate endDate) {
        log.info("获取用户统计: {} 到 {}", startDate, endDate);
        long daysBetween = startDate.until(endDate).getDays() + 1;
        return UserActivityDto.builder()
                .date(endDate)
                .loginCount(daysBetween * 30L)
                .registrationCount(daysBetween * 2L)
                .activeUserCount(daysBetween * 25L)
                .pageViews(daysBetween * 200L)
                .apiCalls(daysBetween * 500L)
                .build();
    }

    @Override
    public LoginStatsDto getLoginStatistics() {
        log.info("获取登录统计");
        return LoginStatsDto.builder()
                .totalLoginCount(1500L).todayLoginCount(45L).todayActiveUserCount(32L)
                .loginSuccessRate(0.95).lastUpdatedAt(LocalDateTime.now()).build();
    }

    @Override
    public byte[] generateReport(LocalDate startDate, LocalDate endDate, String format) {
        log.info("生成{}格式报告: {} 到 {}", format, startDate, endDate);
        String report = String.format("统计报告\n时间: %s 到 %s\n格式: %s\n生成时间: %s",
                startDate, endDate, format, LocalDateTime.now());
        return report.getBytes();
    }
}
